A cooling circuit used in, e.g., a vehicle air-conditioning unit is configured to circulate a refrigerant in passages that extend through an evaporator, a condenser, or the like. Typically, a refrigerant tank is disposed in a middle position of the passages in which refrigerant circulates. The refrigerant tank is configured to store the refrigerant to separate vapor refrigerant from liquid refrigerant. As a refrigerant tank, there have been a modulator tank, which is integrally formed with a condenser, or a receiver tank, which is disposed downstream of the condenser, for example.
Refrigerant may contain water during circulation of the cooling circuit. If such a refrigerant containing water circulates in the cooling circuit, the water may be condensed at an expansion valve, which will lead to occurrence of clogging in the expansion valve. Therefore, it is necessary to remove water from refrigerant circulating in the cooling circuit during cooling cycle operation.
Japanese Patent JP3629819B discloses the condenser integrally having a liquid receiver tank. The condenser has a desiccant in the liquid receiver tank (one type of refrigerant tanks) to adsorb water contained in the refrigerant. The desiccant, which is housed in a bag (hereinafter, referred to as a “desiccant bag”), is disposed in a lower side of the refrigerant tank.
An opening is formed in a side surface of the refrigerant tank to allow the refrigerant to pass therethrough. Such an opening is formed as an inlet to allow the refrigerant to flow into the refrigerant tank or as an outlet to allow the refrigerant to flow out of the refrigerant tank.
More specifically, the condenser described in the Japanese Patent includes the opening as an inlet for the refrigerant that is formed in a side surface of the refrigerant tank facing the desiccant bag. During circulation of the refrigerant in the cooling circuit, a force in a direction away from the wall surface of the refrigerant tank is applied to the desiccant bag due to a pressure by the refrigerant flowing into the refrigerant tank through the opening.
On the other hand, when the circulation of the refrigerant in the cooling circuit is stopped, a revers flow of the refrigerant from the refrigerant tank to an outside may temporarily generate due to a temperature difference in the refrigerant in the cooling circuit. In this case, a force in a direction toward the wall surface of the refrigerant tank is applied to the desiccant bag due to the refrigerant flowing out through the opening. As a result, the desiccant bag is pressed against an edge of the opening by the force.
When the circulation of the refrigerant in the cooling circuit repeatedly starts and stops, the desiccant bag is repeatedly brought into contact with the edge of the opening. Therefore, shearing forces are also applied to the desiccant bag, and as a result, the desiccant bag may be damaged due to the shearing forces.
In view of the above, it is an objective of the present disclosure to provide a refrigerant tank where a desiccant bag is prevented from being damaged.